Manufacture of paper pulp from wood



(No Model.)

G. H. POND.

MANUFACTURE OF PAPER PULP FROM WOOD.

No. 354,981. Patented Dec. 28, 1886.

lna/enlar- UNITED STATES PATE T I Trice.

GOLDSBURY HARDEN POND, OF GLENS FALLS, NEW YORK.

MANUFACTURE OF PAPER-PULP FROM WOOD.

SPECIFICATION forming part ofLetters Patent 3210654331, dated DecemberZS, 1886.

Application filed May 4, 1856. Serial No. 201,100. (No model.)

, and use the same.

My invention relates primarily to the treatment of wood with the sulphides in the'process of making pulp; but other material can be advantageously treated with it.

It further relates to the shortening of the time required to work a charge of sawdust, chips, shavings, or other pieces of wood, or other fibrous material with the sulphides of lime, magnesia, or other sulphides or bisulphides, and also with sulphurous acid; also, to improvements in the apparatus in which sulphurous gas and the sulphides are made, regulating the time required to make and saturate them; also, to improve the mode ofhandling the material after it has been treated in a charge with the sulphurous acid, or the saturated sulphides, so as to facilitate the washing and bleaching of the same. I attain these objects by the mechanism illustrated in the accompanying drawings, in which Figure 1 is a sectional View of a tower with compartments A A A inclosed within the inside walls, B B. O G are openings into the side flues, D D, which are stopped off at the top. E E are doors to cover the openings and direct the gases into the flues or compartments at the will of the workmen. JJare swinging doors under the bars K K, for closing the openings between them, which, with the inside walls, separate and inclose the compartments A A A. a 'a a represent the openings'and doors through the outside wall, through which the compartmentsare charged; F, water-tank; G, the distributer for dividing the water into a spray or fine streams; U, water-pipe to supply the tank; L L, the outside walls of a tower.

Fig. 2 is a sectional view of a digester, M, with supporting-flanges N N, and breakers O 0, upon which the contents of the digester are forced by the pressure of steam through the -from the burning sulphur.

blowoff cock 1?, the steam being directed onto the points of the teeth VV on the body of the breakers. and a receptacle for the charge after it is blown out. R is the receptacle for the liquids from the tower, which is carried out through pipe SJ T is the conductingpipe for the sulphurous gas from the airtight furnace. bis acover to the top of the tower directing any waste gas out through the pipe. j

In the preparation of the sulphides, either saturated or not, compound or single, or of sulphurous acid, I first prepare a receptacle for the purpose constructed in the form of the tower, Fig. 1, of the required height. This tower is divided into compartments A A A, the bottom of each compartment being pr0- vided with bars K K of suitable material to sustainvthe weight placed thereon. Each of these compartments is filled nearly full of common limestone when the sulphide of lime is to be made, and with pieces of any suitable porous stone or other suitable material when sulphurous acid is required. When the sulphide of magnesia or the combination of lime and magnesia is to be made, the compartments are filled with prepared dolomite or other magnesian rock. After the compartments are charged with the alkaline material the doors of the compartments a a are closed tightly and the water turned into the top of thetower in a sufficient quantity to wet the charges in the several compartments as it slowly runs down over the surface of the various pieces of which the charge is composed, preparing it for the reception of the fumes of the sulphurous gas A short distance from the tower is an air-tight furnace (not shown) for burning sulphur, provided with a jet of air under pressure, and directed upon the surfaces of the burning sulphur, forming a very dense mass of the sulphurous gas, and by the pressure forcing it into and up through the tower or other receptacle provided for its absorption or use. The gas is conveyed to the base of the tower in pipe T. This pipe is kept cool by running water or other convenient means, so that the sulphurous gas enters the base of the tower quite cool, and is forced up through the holes andv crevices between the limestone or other material in the various Y is atank inclosing the breakers compartments, being rapidly absorbed by the water as it passes through, forming sulphurous acid, the acid then attacking the lime or magnesia and combining with them, making the chemical required. The quantity of water running down over the charge regulates the strength of the liquid at the base.

The utility of the various compartments is obvious, as the limestone or other rock is decomposed by the sulphurous acid and carried down with the liquid as it flows over it, and if there are no compartments the rock may stop by some obstruction, and then the whole mass settle down at once, breaking through the sides of the tower,-and also the receptacle and the pipes at the base, completely spoiling it until repaired. \Vith the compartments it is impossible to have such damage occur, as each one sustains the weight of its charge on the bars K K at its base. WVith the inclosed compartments in the tower it can be arranged so as to mix or make combinations of the lime and magnesia or other materials or bases as may be required. One compartment. may be charged with magnesia and another with lime, so as to combine them in any proportion required.

In the spaces between the top of one charge and the bottom of the other in the compartments the liquid takes up large quantities of sulphurous gas, therebyaccelerating the chemical changes required to make saturated solution of the sulphides. Theside flue into which at any time when in operation the sulphurous gas can be turned oif from any one of the inclosed compartments by opening the small doors, as at H H, and closing the swinging doors J J, leaving them completely shut off from the others, either for the convenience of recharging or repairing or to cutoff one compartment without interfering with the working of the other compartments in the tower.

In the ordinary way of using the tower or other receptacle for the absorption and combination of the sulphurous gas it is usual to depend upon the draft of the chimney or tower to carry up the sulphurous gas through thev material with which it is charged, making it a very tedious process. WVhere the sulphur is burned in an air-tight furnace under pressure of the air forced in and on to it, the gas arising therefrom can be rapidly conducted in pipes to the receiver provided for its absorption and combination, and then by the continued pressure forced rapidly through the contents of the receiver and into all the small spaces therein. The density and pressure render it much more active, so that its combinations are rapidly made, sh orteningthe time of making saturated solutions many hours. After the sulphides'are made and a sufficient quantity of the liquid of the required strength has accumulated in the receptacle R, at the base of the tower, it is then umpednp into a large tank (not shown) made of or lined with metal that will resist its action and used as follows: Into a digester, illustrated at M, I put a large quantity of either sawdust,

chips, shavings, or other pieces of wood, or other fibrous material, filling it nearly full, then the saturated sulphide is let into it, so as to thoroughly wet the charge and'have a quantity at the bottom of the digester to cover the opening of the steam-pipe a foot or more. After this is accomplished the cover is bolted on, the steam is let in through the steam-pipe, and the steam raised to the required pressure. The sulphides are largely decomposed by the steam and heat, freeing a large amount of sulphurous gas, which, attacking the wood in combination with the remaining sulphides, first softens and then partially separates its fibers. After a few hours itis sufficiently softened and ready to be blown out through the blow-off cock P onto the breakers O 0, where the p eces of wood or other material are completely separated into a fine fibrous mass.

Thebreakers illustrated at O O are cylinders covered with projeeti ng points or teeth inclosed in a tank, Y, revolving on their axes, so as to clear themselves and always present a clean surface and new points to the steam forced upon them. The greater the pressure which forces the stream upon the breakers the more perfectly will the fibers be separated one from the other. By this process the charge is com- 'pletely treated in much less time than by the old way, and it is very soon ready to be thrown onto the breakers, where it is finished by each particle of the fibers being separated from the others by the concussion, instantly preparing it for expeditious washing, thereby saving a great amount of time.

It usually consumes twenty-four hours to treat and wash a charge from the digesterin the ordinary mode of operation with the sulphides, which in this process is accomplished in less than half of that time- What I claim, and desire to secure by Let ters Patent, is

1. In the process of making pulp from wood or other material and the preparation of a solvent therefor, a tower provided with inclosed compartments,each compartmenthavingopenings into side flues with doors for closing or opening them, thereby letting the gases therein into the flues and separating the compartment from its circulation and contact, as described.

2. In the process of making pulp from wood or other material and the preparation of a solvent therefor, a tower provided with inclosed compartments and side flues, with adjustable openings with doors and grate-bars, with swinging doors to close the openings therein, whereby at the will or convenience of the operator all the openings of the compartment can be closed or opened, thereby separating or connecting either compartment with any other or all within the tower, as herein set forth. a

3. In the process of making pulp from wood or other material and the preparation of asolvent therefor, the burning of sulphur in an airtight furnace under a pressure-with a jet of air forced therein and onto the'surface of the sulphur, forming a dense sulphurous gas, the pressure rapidly forcing it into and through the conducting-pipe and the receptacle provided for its use and absorption, as herein set forth and described.

4. In the process of making pulp from wood or other material and the preparation of a solvent therefor, the combination of the tower with inclosed adjustable compartments charged with one or more alkaline bases covered with running water, the burning of thesulphur in an airtight furnace under pressure with a jet of air forced therein, the rapid con-' duction of the dense fumes of sulphurous gas in pipes to the receptacle provided for its-use and absorption, the forcing the circulation of the sulphurous gas by pressure through the compartments and their charges, and the acceleration of its combination with the alkaline base, rapidly saturating it with sulphurous gas, as and for the purposes herein set forth and described. 7

5. In the process of making pulp from wood or other fibrous material, a digester charged with sawdust, chips, shavings, or other pieces of wood or other fibrous material mixed and thoroughly wet with the liquid sulphides saturated with sulphurous gas and kept under the requisite heat and pressure with steam long enough to thoroughly soften and partially disintegrate the pieces of wood in the charge, and then blowing it out of the digester through an opening provided therefor onto the points of the teeth of the breakers, entirely separating the fibers of the material from each other into a fine fibrous mass, as herein described and set forth.

6. In the process of making pulp from wood 7. In the process of making pulp from wood I or other fibrous material, a digester charged with sawdust, chips, shavings, or other pieces of wood or other fibrous material thoroughly wet witha solvent and worked under heat and pressure long enough to soften and partially disintegrate the fibers of the mass, then blowing out the charge from the digester through an opening provided therefor onto the points of the teeth of a revolving breaker, thereby entirely separating the fibers from each other, substantially as herein set forth and described.

8. In the process of making pulp from wood or other fibrous material, the cylindrical breakers revolving upon their own axes, provided with teeth upon which a prepared charge of sawdust, chips, shavings, or other pieces of wood or other material is thrown,with a pressu re of steam or other great force up on the points of the moving teeth of the breakers, thereby instantly separating itinto a fine fibrous mass, substantially as'herein set forth and described.

GOLDSBURY HARDEN POND.

Witnesses:

H. M. POND, L. W. NnLsoN. 

